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NIntegrate::inumr

Details

  • This message is generated when none of the values of the integrand for the sampling points in a region (one- or multidimensional) is a number.
  • Off[message] switches off the message; On[message] switches it on. For example: Off[NIntegrate::inumr].

Examples

Basic Examples  (2)

An error occurs because the integrand contains a parameter that does not have a numerical value:

Wolfram Language code: NIntegrate[Cos[c x], {x, 0, 6}]

The integral is computed without difficulty if the parameter has a numerical value:

Wolfram Language code: With[{c = 1}, NIntegrate[Cos[c x], {x, 0, 6}]]

Here, NIntegrate is used within NMaximize and is evaluated repeatedly without a numerical value for c:

Wolfram Language code: NMaximize[NIntegrate[Sin[c x], {x, 0, π}], c]

One possible solution is to use Integrate instead of NIntegrate. This is advantageous because NMaximize can do symbolic processing on its input:

Wolfram Language code: NMaximize[Integrate[Sin[c x], {x, 0, π}], c]

If symbolic integration is not possible, an alternative is to restrict the argument type given to NIntegrate with NumericQ by writing a helper function fun:

Wolfram Language code: fun[c_ ? NumericQ] := NIntegrate[Sin[c x], {x, 0, π}]

Symbolic input returns unevaluated:

Wolfram Language code: fun[a]

Numeric input evaluates:

Wolfram Language code: fun[1]

Now, using NMaximize on fun evaluates without any warnings:

Wolfram Language code: NMaximize[fun[c], c]